Describe the membrane and cell wall structure of GRAM (+) bacteria.

Thick wall with 3 layers of peptidoglycan. Stains purple in GRAM staining. Only interior membrane. Teichoic Acid are equivalent of LPS but much less frequently cause shock.

12

What purpose does the cell wall serve for bacteria.

Gives rigidity and helps resist osmotic forces.

13

What are some vulnerabilities of cell walls?

They are target by host cell and many antibiotics. Antibiotics will prevent synthesis, lysozyme will cleave wall.

14

Can you vaccinate against LPS?

NO! it is immunogenic and vaccinating against it would only increase it virulence

15

What are the two main components of the glycocalyx layer? What are these layers rich in?

Slime Layer and Capsule. Carbohydrate rich

16

What does the slime layer do?

AttachmentFormation of biofilms (antibiotic resistance)

17

What does the Capsule do for bacteria?

Protective,Antiphagocyticserological testingvaccine targetattachment

18

What are the purpose of pili/fimbrae and how do they differ between GRAM neg and pos bacteria?

Used for attachment and often a virulence factor. Gram pos were only recently discovered and are simple repeating subunits. Gram neg come in many types and are complex, some have evolved into propulsion systems or secretion molecules that are virulence factors in their own right.

19

What causes gram - to resist CV stain?

Outer membrane

20

How do Acid Fast bacteria stain and why?

Mycolic acid layer resists both CV and counterstain...need to use acid fast procedure

21

Is LPS and endo or exotoxin?

Endotoxin

22

What type of GRAM neg pili are used for attachment? propulsion? secretion?

Type1 for attachment, type 4 for propulsion, type 3 and 4 for secretion.

23

Give and example of two bacilli and two spirochetes

Bacillus and vibrio are bacilli, borrelia and treponema are spirochetes